Precision M4700 (and M4800) options for adding a second hard drive for RAID 1 mirrored array

When configuring a new Precision M4700 on the Dell website, the option to use two 2.5" 7200 RPM hard drives configured in a RAID 1 mirrored array is limited to selecting either 320 GB or 500 GB capacities.  Is it possible to install or otherwise retrofit a new or existing M4700 for two larger capacity hard drives (e.g. 750 GB WD Scorpio Black) in a RAID 1 array?  

It seems like the optical bay, where the second conventional hard drive must be installed on a M4700, is limited in height, possibly 7 mm, but I'm unsure if this is correct.  I have had several phone calls and online chat sessions with Dell sales and technical support representatives, but no one seems to be certain if a 9.5 mm high 2.5" hard drive will fit in the optical bay or if there is some other restriction limiting the total capacity of traditional hard drives configured for RAID on the M4700 to 500 GB.  

Can someone please confirm whether or not the optical bay on a M4700 has a height restriction that prevents it from accepting a standard size laptop hard drive such as the 750 GB WD Scorpio Black (WD7500BPKT, Dell Part# A4592575)?  The same question also applies to the new Precision M4800, even though the custom configuration options for 2nd hard drives and RAID aren't available on this brand new model as of today.  Thanks in advance for any help on this issue!